So 16X is no good beyond 600 yards?

I have a Vortex Viper PST 4-16 scope and I am buying rings/bases. At first I was going to buy 20 MOA bases, but now I am reading that some people have problems zeroing at 100 yards with 20 MOA bases, all shots go high even after cranking all the way down.

Anyone ever run into this problem using 20 MOA bases?

It is simply not the case that zeroing a rifle at 100 means that the bullet has reached its highest point of travel.

So far from .223- 338 LM I have not see this happen on my range.

Have your shot paper at both distances? If so, and if you are impacting perfect center on a 1" dot at 100 yards are you still perfect center on a 1" dot at 200 yards?

Not trying to be rude, or make it out like you're lying, just trying to wrap my head around what is going on.

The way you are thinking about it is as if your scope is perfectly parrallel to the ground and you are raising the barrel to where the scope is, if this were the case then yes you would create an arc and it is possible to have a 100yd Point blank and a 200 yd point blank

Buckets are not affected by gravity, mind blowing I know. NASA proved that theory.

I assume you meant bullets.

Please show me NASA's data, because that is exactly opposite of what I have been teaching for years.

And I think you are remembering something wrong.

Bullets are affected by gravity, mind blowing I know. NASA proved that theory. If you are shooting up hill and don't account for the degree of the angle you will shoot under the target. If you are shooting downhill and don't account for the degree of the angle you will shoot under the target, again mind blowing. It took me a while to understand these facts.

Give me a little while so I can try and draw it out

BP go back and read your notes on shooting on incline again. You will find in both cases (uphill and downhill at great angles) your POI will be high.

I have not had any problems zeroing. The one thing I had to navigate was why I had the same POI at 100 as I have at 200. I finally figured out the obvious, that it had to do with my bullet still rising at 100 yards.

Could this ^ have anything to do with the use of the 20 MOA base, or is it caused by something else? I'm not at all complaining about it... just curious.

jdk, I may have missed it....how high is your scope above the bbl?

This is caused by the difference in height of axis of scope and axis of bore. Your barrel has to be point upward to allow for the bullet drop that occurs before reaching target, and also to make up for difference in height of scope above barrel (LOS versus LOD). Your Maximum Midrange Height is past your First Zero (100 yards in this case) and it just happens that your ballistic components and bullet drop make your Second Zero 200 yards. So Your Mid Range Maximum Height is probably around 160 yards and probably around +1 to +1.5 inches.

This is your bullet flight or path for these components.

Bullets do not rise, ever.

Zeroing is making what the scope "sees" match where the bullet is, in its' arc path. Creating a 100 yard zero is actually pointing the barrel skyward so that the bullet and the scope are on the same plane at your zero distance, in your case, 100 yards. Anything beyond the zero mark, the bullet is falling, but how much depends on BC and MV. So if you are saying that your bullets are still exactly in line from 100 yards to 200 yards (which I have a hard time believing they are exactly the same) then your bullet is not falling as much as others do at 200 yards.

No the 20 MOA base has nothing to do with any of this. The 20 MOA base creates the upward cant of the rear of the scope, mirror image of the upward cant of the muzzle, so that when the scope is zeroed for 100 yards you have more available elevation travel left in the erector of the scope that allows the ability to dial elevation corrections for long range.

If we could mount a laser exactly parrallel to the bore of a rifle, on top of the rifle imitating what the scope sees, and shoot one from the bore of the rifle. At 100 yards they would be the same vertical distance apart as they are on the rifle. But we want the bullet to hit exactly where the center of the reticle is looking at a predetermined distance, therefore the need to cause upward deflection of the bullet arc from muzzle to zero distance, since bullet do not travel like a laser beam.